概述

特别提醒

版本5.7

查看数据库当前版本：

select @@version;

关键词: B+树 Innodb

基本概览

schema

在MySQL中，schema 和 数据库（DATABASE）是同义的。

In MySQL, physically, a schema is synonymous with a database. You can substitute the keyword SCHEMA instead of DATABASE in MySQL SQL syntax, for example using CREATE SCHEMA instead of CREATE DATABASE.

DDL

DDL is Data Definition Language statements. 数据定义语言，用于定义和管理SQL数据库中的所有对象的语言。例如：

1. CREATE - to create objects in the database 创建
2. ALTER - alters the structure of the database 修改
3. DROP - delete objects from the database 删除
4. TRUNCATE - remove all records from a table, including all spaces allocated for the records are removed

DML

DML is Data Manipulation Language statements. 数据操作语言，SQL中处理数据等操作统称为数据操作语言。例如：

1. SELECT - retrieve data from the a database 查询
2. INSERT - insert data into a table 添加
3. UPDATE - updates existing data within a table 更新
4. DELETE - deletes all records from a table, the space for the records remain 删除
5. CALL - call a PL/SQL or Java subprogram
6. EXPLAIN PLAN - explain access path to data

DCL

DCL is Data Control Language statements. 数据控制语言，用来授予或回收访问数据库的某种特权，并控制数据库操纵事务发生的时间及效果，对数据库实行监视等。例如：

1. COMMIT - save work done 提交
2. SAVEPOINT - identify a point in a transaction to which you can later roll back 保存点
3. ROLLBACK - restore database to original since the last COMMIT 回滚
4. SET TRANSACTION - Change transaction options like what rollback segment to use 设置当前事务的特性，它对后面的事务没有影响.

MySQL Connector/J 8.0 Developer Guide

Configuration Properties

官方文档 (opens new window)

• allowMultiQueries

Allow the use of ';' to delimit multiple queries during one statement (true/false). Default is 'false', and it does not affect the addBatch() and executeBatch() methods, which rely on rewriteBatchStatements instead.

Default Value false Since Version 3.1.1

参考文档

• 官方文档 (opens new window)